"One of those affected, Sofia Enciso, a resident of El Salto and environmental activist, described the findings in her family’s results. “At least, both in my results and in those of my children, all show some traces of mercury, lead, arsenic, cadmium, chromium, aluminium, and nickel. All show at least a percentage,” she said. Researchers say the contamination is directly linked to industrial discharges into the river system. According to Alejandra Guerrero, a researcher at the University of Guadalajara, pollution in the Santiago River is “a consequence of wastewater discharges,” and she warned that the situation has reached a critical point. “I can tell you that we are in a warning zone. What is happening in El Salto requires deep attention because people are dying from what is happening in that region, and it requires urgent attention,” Guerrero said. Residents have repeatedly demanded action from local and state authorities, citing years of exposure to contaminated water, air, and soil. In response to the findings, Hector Raul Perez, Secretary of Health of the State of Jalisco, urged those who tested positive to seek medical assistance. He called on affected residents to visit clinics and laboratories in order to begin appropriate treatment and monitoring. The Santiago River has long been considered one of Mexico’s most polluted waterways, with communities along its banks warning that industrial waste has created a public health emergency that remains unresolved."